This present invention relates to an automated robotic station for crystallization of proteins and other biopolymers via the sitting drop vapor diffusion and micro-batch methods.
In order to visualize the three dimensional structure of proteins and other biopolymers via x-ray diffraction crystallography, one must grow quality crystals of the biopolymer. Unfortunately, the science of protein crystal growth is currently incapable of predicting the conditions under which a particular protein will crystallize. Thus, as with many combinatorial problems, one must search a high dimensional parameter space (large number of possible recipes) to find the solution (optimal crystallization conditions). Often the brute force approach of preparing and screening many experiments is the most effective method. This is extremely labor-intensive and time consuming. Thus, preparing quality protein crystals remains the bottleneck for elucidating the structure of proteins via x-ray diffraction crystallography. As a result, there has been significant effort to automate this process.
Machines that dilute stock solutions and dispense protein and other ingredients into chambers for crystal growth have been available for some time. Recently, machines have been developed which automate additional steps in the process of protein crystallization. However, despite recent attempts, these machines require several manual steps and are not capable of achieving high output. For example, operators must manually feed empty crystallization plates and remove completed ones. Thus, the process is limited to filling at most a handful of plates without operator intervention. Also, these plates must be removed quickly by the operator to prevent degradation of substrates due to lack of temperature control. In addition, most machines search for crystallization conditions for one protein at a time and only utilize a handful of ingredients simultaneously. Lastly, many of these machines utilize plates with only twenty-four wells, where each well represents a single crystallization experiment. As a result, these machines are capable of producing dozens (not hundreds or thousands) of experiments for a single protein and are limited to exploring a few ingredients. Thus, they are not capable of preparing large numbers of disparate combinations for multiple proteins, which is necessary for effective high output crystal screening.
It would be desirable to develop a machine that can prepare vast numbers (on the order of thousands) of unique crystallization experiments, which contain many combinations of ingredients for multiple proteins, in a realistic time frame and in a fully automated manner. In particular, this machine must be capable of automatic feeding of many plates (of various capacities including 24, 96, and potentially 384 wells) individually, dispensing small volumes of solutions accurately, sealing crystallization experiments, and storing completed plates in a temperature controlled environment. This process should be accomplished completely under microprocessor control, based on recipes custom designed by the operator via special software. Lastly, this machine should be able to interface with future intelligent systems that quantitatively asses crystallization experiments and modify the design of future experiments.
The object of the present invention is to provide a fully automated high output robotic station for the crystallization of proteins and other biopolymers via the sitting drop vapor diffusion method and microbatch technique.
This is a table mounted robotic station capable of preparing crystallization experiments specified by the operator via software. The entire process is fully automated, from the loading of the empty microplates from the magazine, to the storage of the completed microplates in a temperature controlled hotel. The magazine and hotel are capable of holding approximately thirty 96-well (as well as 24-well and potentially 384-well) microplates, thus allowing the user to carry out approximately 3,000 experiments in a single cycle.
The station utilizes the following components: a mechanism for automatic loading and positioning of microplates; a fluid dispensing system that includes reagent bottles, fluid transport lines, and a probe(s) for the delivery and pipetting of small volumes of protein and ingredients; a system that seals the crystallization experiments with tape; and a hotel for storing completed microplates in a temperature controlled environment.
The accompanying drawings in conjunction with the detailed descriptions will provide further evidence of this machine""s advantage over existing technology.
Other advantages of the invention will become apparent from a perusal of the following detailed description of a presently preferred embodiment of the invention taken in connection with the accompanying drawings.